


Mutation

by less_than_wholesome, meshkol (ashernorton)



Category: Captain America (Movies), Iron Man (Movies), Marvel Cinematic Universe, The Avengers (Marvel Movies)
Genre: Ambiguous/Open Ending, Capwolf, Come Inflation, Dry Orgasm, Dubious Consent, Dubious Morality, Fuck Or Die, Human-Werewolf Interactions, Knotting, M/M, Marathon Sex, Multiple Orgasms, Non-Consensual Body Modification, Prostate Milking, Rape/Non-con Elements, Size Kink, Werewolves
Language: English
Status: Completed
Published: 2020-03-20
Updated: 2020-03-20
Packaged: 2021-02-28 18:54:46
Rating: Explicit
Warnings: Rape/Non-Con
Chapters: 1
Words: 11,523
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23232028
Author URL: https://archiveofourown.org/users/less_than_wholesome/pseuds/less_than_wholesome, https://archiveofourown.org/users/ashernorton/pseuds/meshkol
Summary: During a raid on a HYDRA base in Germany as the Avengers look for Loki's sceptre, a villain injects Steve Rogers with an unknown serum and turns him intosomething else, something massive and insatiable and powerful.Tony learns this the hard way.
Relationships: Steve Rogers/Tony Stark
Comments: 11
Kudos: 411
Collections: MCU Kinkbang 2020, Stony*, v hot





	Mutation

**Author's Note:**

> Hey look, an addition to the amazing [MCU Kink Bang 2020](https://mcukinkbang.tumblr.com/) fest going on. Three cheers to the mods for putting it on yet again, and allowing me to participate.
> 
> Art is done by the magnificent [less-than-wholesome](https://less-than-wholesome-shipper.tumblr.com/). Loved the very inspiring art, and I'm so pleased that we got to work together on this Capwolf fic. Hopefully the finished result isn't a total disappointment.
> 
> This fic is going up despite the fact that it's still going through active beta -- normally I'd already have this done, but I'm an epidemiologist and all-source analyst so I've been... _really-really-really fucking busy_ for the past few months. For obvious reasons, I suppose. I do apologise for any mistakes that haven't been caught yet, and I'll be updating the content with the edits once I receive them (and have another second to sit down, whenever the fuck that may be), but hopefully it's decent enough for public consumption.
> 
> Happy reading, and stay safe, dears.

Tony’s not entirely sure how it happens, because it seems like it happens so _fast_.

One second, he’s fighting like everyone else, multitasking by kicking some serious HYDRA arse as he scans the far-distant base for any shielding or irregularities, which could be the indicator they need for if this is the home of their prize. The mission is the sceptre, after all, and with his suit as well as JARVIS’s eye from satellites, he’s the most qualified to take point on that particular job while the rest of the Avengers clear the area of combatants.

The next second, he hears Steve cry out through the comms, a loud and pained sound that echoes in Tony’s ears, and he’s already beelining in Steve’s direction before he realises that he’s doing it.

“ _Is Cap hit?_ ” he hears Clint shout over the clamouring of fighting and the sound of Steve choking on something, something wet and horrible. The others echo Clint’s barking question through their own comms, and he hears Natasha give the order for someone to move to Steve’s location.

“On it,” says Tony, heart in his throat as his vision goes even sharper with single-minded focus, darting around trees as he shoots towards Steve’s location, blinking in bright blue on his HUD. He’s the closest, and while he’s supposed to be primary on scanning the HYDRA base, Thor and Natasha are just as capable as he is. Tony blasts a few goons barrelling through the trees as he asks urgently, “Cap, d’you read? What’s your status?”

The only thing that replies is gasping breaths that are almost moans of what sounds like pain, and he can hear the distant sound of the forest floor being torn to pieces as if Steve’s on the ground, thrashing and God knows what else, before there’s an ear-splitting screech of interference and the comm goes dark. In response to the radio silence, Tony directs all power to his thrusters, ploughing entirely through trees instead in his haste to get to Steve’s location.

All he can think of is quiet nights in Avengers Tower, Steve laughing at films the rest of the team has decided is imperative for Steve’s twenty-first century education, Steve trying to convince Tony to accept a monthly payment from his military back pay in order to cover rent as well as the frankly obscene amount of food he consumes and frowning when Tony rolls his eyes, Steve painstakingly refurbishing things that he accidentally breaks like the microwave when he accidentally nukes aluminium foil or doors when he forgets his own strength – so many little moments that are integral to their team, their _family_ , and Tony has to get there in time, has to help in any way he can, even if it kills him.

He sees Steve on his HUD earlier than he would with his own two eyes, and there’s definitely something wrong; Steve’s body is almost bulging and it’s clear that he’s seizing, mouth open in a silent scream behind the cowl. The shield is on the ground next to him, a smear of blood across the white star, and the person who’d clearly gotten on the wrong side of it is lying unconscious to the side, blood oozing from her head. Tony shoots off an electronic net to restrain the hostile indefinitely a few seconds before he slams onto the ground with a loud boom, and JARVIS is rattling off Steve’s vitals – heartrate skyrocketing, hypertension, temperature spiking dangerously – as he advances, panting with exertion and adrenaline.

“Steve,” he says hoarsely through the suit, armoured hands reaching for Steve’s thrashing form as he falls to his knees heavily. He holds him down, unsuccessfully at first because Tony doesn’t want to hurt him, and then more successfully when he pushes more power into his suit to withstand the force of Steve’s enhanced body thrashing.

“ _Status!_ ” he hears Natasha shout over the screech of fighting through the comms. There’s an explosion, one that Tony can feel even through the ground he’s knelt on, and his earpiece is white noise for a long moment before it goes back to the sounds of fierce fighting.

Tony’s brain is whirling with solutions and probabilities and hypotheses, trying to figure out what’s going on and how he’s going to get Steve safe and stabilised out of a mini warzone, as he replies through the tight ball of anxiety in his chest, “Cap’s down – some sort of fit. He needs to get out of here ASAP, and preferably to a hospital. I have no idea what the fuck is happening. Might be some sort of nerve agent?”

“ _We’re pretty bogged down here_ ,” Clint says, out of breath. He grunts, heaves, and then the familiar sound of a bow releasing tension sounds before yet another explosion goes off, clearly from one of his exploding arrows rather than a building going up. “ _Thor, you read?_ ” he adds, loudly enough to be heard through the roar of the Hulk in the background of someone’s comm.

“ _I do read, Barton, and I can certainly take the Captain to a medical facility if you would prefer_ ,” Thor says, electricity crackling and making Tony’s ears ring from the sound of it, almost but not quite covering up the sounds of fighting and Steve choking on his own saliva, his skin bright red and his eyes bloodshot. Tony’s practically hyperventilating now, half out of fear and the other half from the sheer exertion he has to apply just to keep Steve from hurting himself. “ _That being said, Stark would be faster than I, and will certainly be able to get him to an appropriate facility as I do not have the knowledge of where_ —”

That’s enough for Tony, and he takes stock of Steve’s seizing body to work out how to stabilise him enough to fly them both without Steve destroying the suit. The closest is Landstuhl he thinks, only about fifty kilometres northwest he thinks, so he tries to get his laboured breathing under control before he interrupts, “Got it. Taking him to Landstuhl outside of Ramstein, so meet us there.”

“ _Anyone good for cover?_ ” Natasha asks in between the buzz of her tech of the crack of her guns discharging.

“We’re clear over here,” Tony says, gritting his teeth while he tries to get Steve secure in his arms, mentally praising JARVIS as he wordlessly sets a coordinate point on the Avengers’ private cloud and pulls up a flight plan. “The bastard who got Steve is contained at the marker, so as soon as you’re in a good place to send someone, get this motherfucker to Landstuhl so we can figure out what the hell she did. Until then, be safe everyone, and kick some serious ass for us, yeah?”

There’s a chorus of affirmatives and Tony bolts off, his flight erratic due to Steve’s powerful convulsions but ultimately quick, but he only makes it about ten kilometres – well outside of comms range unless JARVIS manually hooks into satellites – before everything goes completely insane at breakneck speed.

First it’s JARVIS’s shout of surprise, followed almost immediately by Tony’s already-tenuous grip on Steve becoming impossible to maintain – the mass of Steve’s body increases exponentially and he’s actually _growing_ , his body changing right in front of Tony’s eyes in a way that his overstressed, anxiety-ridden brain simply can’t compute. The explosion of hair and muscle and changing bones is so sudden that Tony’s numb fingers slip without being able to stop it, and Steve’s in freefall, his density ensuring that it’s fast even as he mutates in mid-air.

Tony doesn’t even register that he’s changing course and rocketing downwards until he’s already halfway to Steve, the inversion of direction so sudden that his vision tunnels from the g-force, nearly knocking him unconscious. It’s mostly JARVIS’s manoeuvring that allows him to get his arms around the massive bulk of...whatever in the _fuck_ Steve’s mutating into, somehow hooking his arms around what he vaguely thinks might be Steve’s waist. He doesn’t have time to even figure that out though because JARVIS is putting every iota of power into the thrusters, trying to get the suit to negate the downwards velocity so they don’t _die_ on impact, his suit flashing with warnings and JARVIS yelling _hold on sir brace for impact!_ All Tony can do is try his damndest to hold on, twisting his body as much as JARVIS will allow him to so he’s underneath the massive, hair-covered bulk.

When they hit the ground, hard and jarring, and Tony thinks he blacks out from the sheer impact on both sides, the entirety of Steve’s mutated weight landing directly on his chest – one second there’s an explosion of pain and pressure from the crash, the gel substance that lines his undersuit expanding as it absorbs his impact before it bursts entirely, and the next second he’s being attacked by something he cannot see, his suit utterly dead and eyes stinging from sweat, gel, and fuck knows what else. Whatever it is – _Steve?_ – tears at his armour with ear-splitting screeches of metal, and it has to be Steve, has to be, because there’s no one else on the planet except some of the X-Men and specialised robots that could rip it off like this, his entire body jerking from the force and his heart a racing flutter in his chest, his lungs burning because he can’t breathe, he can’t _breathe_ , the gel and fear and disorientation clogging his throat—

The faceplate of his suit is ripped off, a distant sting of pain along his left cheekbone registering to his overwhelmed and overextended brain, and he’s instinctively coughing up gel and saliva even as he tries to push the heavy _thing_ off of him. It’s completely ineffectual at first, only chunks of the armour on his chest ripped free and his arms trapped by what feels like heavy, hair-covered limbs, but then the weight is gone as whatever’s holding him down starts tearing at the plating on his legs and groin, little flickers of stinging pain that barely register through the wild adrenaline coursing through his body. He takes the opportunity to kick his legs out and _at_ whatever Steve’s mutated into – because once Tony wipes at his eyes just enough to slit his eyelids open for a visual, it’s obviously Steve, his uniform shredded from the mutation and brightly contrasting to his powerful, muscular, gold-furred body that’s almost reminiscent of a massive wolf and what in the _fuck_ is going on – but that’s about as effective as anything else has been, Steve’s changed form still just as strong and intense as he is when he’s _not_ some sort of fucking _dog_ —

All of the armour along Tony’s front is completely ripped off in short order, even despite Tony’s frantic efforts to stop it, and he can hear Steve growling, a low and rumbling sound that makes every single hair on Tony’s body stand on end despite the thick gel weighing it down. The fear is bright and wicked, Tony still choking on lingering fluid even as he hyperventilates, and he hears himself gasp out a high-pitched “ _Steve!_ ” when Steve’s limbs – _paws?_ – scrape at him once, the force of it making Tony roll twice before he’s on his stomach, completely out of the armour now and helplessly unprotected, his undersuit in tatters and leaving him mostly naked except scraps of shredded fabric. He tries to scramble up, tries to _run_ , but he barely even makes it to his hands and knees before Steve’s _there_ , his wolf-like body mounting him and pushing his face and chest hard into grass-covered ground, a sharp rock cutting into his already cut cheekbone with a bright bloom of pain.

For a seemingly long period of time, his brain simply cannot compute what’s happening even as he feels Steve’s massive body moving against him, and all he can do is try to brace himself so his entire face doesn’t scrape into the ground, his heart racing and time feeling like it’s simultaneously too fast and too slow. He can feel as much as hear Steve growling and whining against his back, the vibrations buzzing under his skin, and the blond fur coating Steve is soft against the exposed skin of his neck, his back, his arse, his thighs. There’s something about this that is vaguely familiar, and his fuzzy mind tries to dissect it through the adrenaline and fear, Steve’s heavy panting so very close to his ear.

“Steve,” he whispers once, right as everything _finally_ snaps into place, right as his unprepped hole is slightly breached by a slick, hard point that’s gone just as fast as it’d slipped inside, and oh _fuck_ —

Tony completely loses it. With no thought to self-preservation, he feels his entire body flood with a heady surge of adrenaline and fear-based strength, trying his damndest to _get away_. He nearly succeeds, Steve nearly sliding off of Tony sideways onto the nearby boulder and allowing Tony leverage himself to his palms, but then there’s gentle, though very insistent teeth around the back of his neck while Steve’s limbs tighten around his body, pushing Tony’s chest and face back down to the grass and dirt. His prick slides along the crease of Tony’s arse and sporadically slipping painfully into his arse once, twice, and then one final time before Steve _whines_ , hot liquid flooding inside Tony’s hole and allowing Steve’s prick to hammer in deep with a few additional punishing thrusts. Tony can _feel_ Steve’s prick throbbing with orgasm, Tony’s gut clenching as pulse after blistering hot pulse soaks his insides, and Steve’s _still_ trying to get in deeper with hard thrusts of his hips, a thick bulb of flesh ensuring that he can’t and oh _god_ that’s a fucking knot isn’t it, he’s heard of this before during drug-fuelled kink parties and vaguely horrifying YouTube videos he’d stumbled into after hours upon hours of _Watch Next_ surfing during bouts of sleepless inactivity.

He doesn’t dare move though, the teeth around the back of his neck unyielding and impossible to ignore, and he just doesn’t know if Steve’s so far gone and mutated that he won’t gouge out Tony’s jugular or attack him entirely. He just stays as still as possible, his entire body shaking and threatening to collapse completely, and he can feel hot tears streaming down his face and the point of his nose. He watches the leaves on nearby trees flutter in the gentle breeze and tries not to focus on the ache inside him, his hole throbbing from the abrupt intrusion and come leaking down his scraped thighs despite Steve’s prick still lodged inside.

Steve’s teeth slide away, scraping his flesh gently and making gooseflesh flare out across Tony’s skin, and Tony pushes his upper body to brace his weight on his forearms before he whispers in a small, weak voice, “Steve? Steve, are you with me?”

Steve’s cold nose drags up Tony’s damp neck, the sounds of his deep inhales loud in Tony’s ears, and then his hips start jerking again, slow at first before picking up speed. It feels deeper and more misshapen this time, the pain at his rim spiking sharply before it dulls quickly, and Tony knows that it’s because the knot’s deflated now, allowing the entirety of Steve’s prick to pound inside his body, every thrust accompanied by the soft fur inside Steve’s hips. The lewd squelch of his still-hard prick thrusting into Tony is even louder, his insides drenched with Steve’s come, and Tony shudders violently, fingers digging into the grass and dirt to keep his balance as Steve starts thrusting harder and harder and _harder_.

He wants to try to escape again – towards his suit to find something not destroyed so he can call for help, towards the villages and roads that dot the German countryside, _anything_ – but all he can think about is the memory of sharp teeth against his vulnerable neck, about the poor civilians that might get attacked if someone gets in Steve’s way. So he presses his lips together, eyes clenching shut as he takes it, takes _Steve_ , surrounded by the massive bulk of Steve’s mutated form and the echo of Steve’s pants ringing in his ears, making a massive effort to relax his trapped body in a desperate attempt to keep himself from being injured from it all. He has to do anything to make this easier on himself if only so he doesn’t end up in hospital himself, and even though his insides are coated with come, Steve’s prick is still massive, his thrusts brutal. Tony’s fully aware that if he doesn’t relax, he’s going to end up getting severely hurt, even with the heavily modified Extremis he still has swirling through his bloodstream after his reactor surgery.

After what feels like a year, as if from very far away, he registers that his body’s responding now that he’s untensed. It’s unsurprising, really, despite the situation – Tony has always loved getting fucked, has always loved getting held down and pseudo-forced into taking it as brutally as possible, and Steve’s prick is so unbelievably thick and long that it rakes against his nerve-rich insides and along his prostate with every punishing thrust inside. And he’s not going to lie, he’s always fantasised about Steve bending him over and making him take it, because it’s _Steve fucking Rogers_ , the epitome of human perfection and one of his closest friends to boot, even if he’ll never be more than that ( _God he wishes it could be more than that_ ). So he supposes it’s expected that his prick is swollen and leaking onto the grass beneath them, that he’s swallowing moans as pleasure and just-right pain radiates from his arse to even the tips of his fingers as he creeps closer to orgasm, that his body is instinctively pushing back into Steve’s thrusts just slightly even though he tries to make himself stop.

God, but he wants to touch himself. He’s not hard really, the lack of stimulation on his own prick ensuring that he doesn’t stiffen up past a sensitive swell, but he wants to snake a hand beneath him so he can fondle himself. He’s dripping from the prostate stimulation, balls heavy underneath him, and it wouldn’t take much to stroke himself to a full erection. He doesn’t though – it takes all of his energy to keep himself on his aching knees and forearms, weighed down by Steve’s dense heft and completely swallowed by pleasure, and he knows from personal experience that once he fully gets off, it’ll be _excruciating_ if Steve continues to fuck him. Maybe if he was twenty or thirty years younger, sure, but he’s damn near fifty, and his mutilated heart and lungs won’t be able to take the strain even with Extremis.

The last thing he needs is a cardiac episode on top of everything else.

Still, the fear for the situation and Steve’s condition is still bright and he _hates_ this, because he’d wanted something like this to happen in the comfort of the tower, his legs splayed wide so he could watch Steve’s face twist with need as he hammered his prick into Tony’s willing body, blond hair sticking to his forehead and looking so fucking gorgeous that it takes Tony’s breath away just imagining it. This, though, this is all wrong, and he wants it to be over already, wants _his_ Steve back, not just for himself but for Steve too. There’s no way that Steve would ever do something like this without his partner’s consent, and whatever that motherfucker did to him is cruel and horrifying, twisting him physically and mentally until all he’s capable of doing is rutting into Tony, his odd-shaped prick so unbelievable large that he doesn’t even slip out once.

The first orgasm hits Tony hard, his thoughts ripped away in exchange of nothing but sensation, and _fuck_ , he can’t stop the thick moan that tears out of his throat as his body shudders with pleasure, tightening involuntarily as he rides the heady wave of it. Steve whines again, loud and sharp, and pummels his hips harder, _harder_ , making Tony’s orgasm stretch out until he’s shaking and still desperate, dripping with sweat and involuntary tears. His heart is fluttering erratically in his chest and Tony feels like he’s going to pass out, mind blank except _oh-god-yes-fuck_ while he drives his hips back urgently, everything shivery and over-bright as he’s fucked through it.

It ebbs and Tony nearly collapses, heaving for breath and choking on his own whines, the sensations too much and yet not nearly enough. His body is like an electrified wire, his arms shaking so badly that he feels like he’s going to fall, and _fuck_ he’s already getting close again, the brutal thrusts along his swollen prostate unceasing and deliriously pleasurable. He curls his hands into fists against the grass and beats once at the ground, meeting Steve’s thrusts with abandon, and he can feel his prick swelling despite the fact that it’s untouched. Fuck, but he needs to touch himself, just a little, just to take the edge off and—no, he _can’t_ , he knows he won’t be able to stop if he starts, and he’s so wobbly that he’ll definitely fall.

The second crest knocks the breath clean out of him, a sharp cry echoing through the trees and the small lake nearby, and there’s a high ringing sound in his ears now, deafening and shrill. He does fall this time, managing to jerk his left arm just enough land on his forearm rather than smashing his face into the grass, and Steve follows him downwards, his front paws scrambling at Tony’s waist to keep his arse in the air. The angle inside shifts, dizzyingly painful for two thrusts before Tony’s moaning out a garbled, “Oh _fuck_ , yes, God, _please_ , right there Steve, please, _please_.” His right arm snakes beneath his body, brushing the soft fur on Steve’s thick front legs as he grips his half-hard, dripping prick without being able to stop himself, the first stroke making his ongoing orgasm heighten to the point where his vision goes spotty along the edges. He can feel liquid on his forearm, from the sweat that’s dripping down his face to the tears that won’t stop to the drool he can’t swallow, and he bites down on his arm _hard_ , sobbing and moaning and hating that this is happening even though he never wants it to stop, never, God, he wants this to last forever.

He’s being shoved through the dirt as Steve pummels his battered, sloppy insides, knees stinging and painful and his left forearm feeling like it’s being shredded from the occasional rocks beneath the grass, but he doesn’t fucking care – the pleasure is too overpowering, the orgasm ebbing just barely and already starting to spike again as he jerks himself off desperately, his fist wet from his dripping slit and his balls tight against his body. He can feel the prick inside him swelling again, the base of it catching on his sore rim, and it’s so _painful_ and yet so fucking _good_ , like a claim, full and overwhelming and—

Steve howls and thrusts erratically against Tony when the knot swells impossibly big, locking him inside Tony’s body completely with a bright flash of stabbing pain that just feeds into the pleasure. Steve’s hips shallowly jerk into Tony’s insides, the knot so big that it presses and grinds against Tony’s prostate, and then he vividly feels it start actually _pulse_ along it just as come begins to flood his insides, so much of it combining with the previous load that Tony’s lower gut feels like it’s being stretched to the point of tearing open, and Tony _screams_ , loud and sharp, when his orgasm slams into him like goddamn mountain. His entire body is convulsing while he spurts over his hand and the grass beneath him, devastating and violent, every muscle in his body overextended and seizing and burning with exertion. He hears Steve howl again when Tony clenches around him and somehow there’s _more_ come, and his stomach cramps painfully as it distends even further, the intensity of everything in combination blacking out Tony’s vision completely.

He comes down fast and hard, his shaking hand falling from his oversensitive prick to the wet spot beneath him, and Steve’s still jerking his hips back and forth, his prick lodged inside tightly and continuing to spurt come. It’s too much, too fucking much, too fucking _painful_ , and Tony can hear a strange sound through the shrill ringing in his ears that he doesn’t even realise is his own sobs until he eventually registers that he can’t breathe from the force of them. Steve whines, a hot and rough tongue licking at Tony’s damp neck and the back of his head, and finally – _finally_ – his hips still, except he doesn’t though, because Steve shuffling backwards off Tony as if he’s trying to escape.

That is fucking excruciating now that he’s sated, just like he knew it would be, and Tony lets out a pathetically small scream as the knot pulls at his rim. He scrambles up as much as his watery limbs and bloated stomach will allow in an unconscious, desperate attempt to make him _stay put_ , his left hand snapping behind him to try and hold Steve in place while he holds himself up with his soaked right, because the knot’s too big to pull out now, he’ll tear and rip and he _can’t_ — He sobs out another scream when Steve manages to turn himself around, his entire lodged prick twisting inside him in a sloppy, agonising glide against his painfully oversensitive prostate and battered insides. Then, after what feels like a year of shuffling and manoeuvring, Steve finally settles, his tail intermittently batting against Tony’s side and arse as he calmly begins licking at his paws, resting on the boulder behind them languidly.

Tony collapses as much as he can, arms curled up beneath him and his cheek pressed against the grass and dirt, and just _cries_.

* * *

Tony’s so wasted that he barely even reacts when Steve takes him again.

He can’t even cry anymore – he just lets it happen even though it’s unbearably painful and raw, covered in sweat and dirt and blades of grass and long blond strands. He suffers through it, letting out small sounds of pain with every brutal thrust inside, and then chokes out a dry sob when the knot expands again, another flood of come making his guts cramp constantly as his belly distends even further. After he settles again, this time on top of Tony, Steve bathes him, licking at the sweat on his neck and back and arms, teeth occasionally scraping along his flesh.

He drifts, the distant sounds of battle disappearing into the gentle sounds of the forest and lake around them, and he wonders vaguely how long it’s been. He wonders if the Avengers found the sceptre, if they’re en-route to Landstuhl, if they’ve already arrived to find that Tony and Steve aren’t even there, if they’ve sent out a hunting party yet. He’s lost the ability to care that Steve is perpetually inside of him, keeping his seed inside Tony’s aching and bloated body because he never lets his prick out, and it’s a detached thought that his teammates are going to see him like this, naked and battered and scratched up, dried blood and dirt caking the cuts in his skin and his stomach bulging from come. God knows that Natasha’s seen him in various stages of debauchery now, and both Clint and Thor won’t even bat an eye; Bruce might freak out, but it’s relatively safe to assume that he’s probably passed out by now, the strain Hulk takes on him enough to force him into a near-coma when he snaps back to size. Or maybe he’ll Hulk out again, which might be good because God knows that only the Hulk (or possibly Thor) could even hope to get Steve off Tony in between knots.

When Steve’s knot goes down for the third time and his hips begin thrusting once more ( _no-no-please-stop_ ), pummelling into his insides hard and mercilessly, he zones out completely again, his throat so sore from screaming and crying and begging that he doesn’t make a sound. Despite the pain and exhaustion and sloshing come in his gut, he’s apparently recovered enough that it feels somewhat good again despite the cramping; he doesn’t have the energy to move his body into the thrusts at all, extremities numb from being bent at the knees for so long, and time seems to warp, pleasure warring with agony and all of it so very confusing inside his muddled brain. His soft prick swings between his legs, dripping out precome just from the prostate stimulation, and even though it feels so very good all the sudden, he hasn’t a thought to touch it – the sheer suffering he’d dealt with after the previous full orgasm is more than enough to dissuade him of that notion.

Something prickles in the air, a feeling that Tony’s wasted brain is incapable of processing, and there’s a loud snarl at his back, a snap of teeth, a bellow of surprised pain, and then Steve’s _gone_ , Tony’s _free_ , and all he can do is collapse on the destroyed ground beneath him, hot fluid gushing out of his body with torturous cramps until he’s empty, blissfully empty, and Natasha’s face is swimming in his blurred, blackened vision as he gasps for breath.

“It’s okay, Tony,” she says, far away to Tony’s ringing ears, slim fingers hesitating before they stroke through his sweat-dampened and dirty hair. “We’ve got you.”

Tony passes out.

* * *

Tony pokes at his green jello with a fork and does what he does best: hyperfixate and overthink.

The dry facts and tentative suggestions had been the ultimate result of Tony waking up in the infirmary at the tower (three days gone due to heavy sedation as he’d been put through the Cradle for internal work as Extremis took care of the rest), immediately demanding to find out what in the hell had happened to Steve, scoffing at all the soft platitudes of _you should rest Tony_ and _we can talk about this later you know_ and _don’t worry about Cap we’re taking care of it_ , and then going on a rant about how he wasn’t a fucking China doll and would someone just give him information for fuck’s sake?

After his explosion, his heart monitor shrieking until Bruce had finally switched it off, they’d all sat in a charged silence until Rhodey had said point-blank, “He deserves to know, and even if you try to keep this shit from him, he’ll just find a way to escape and hack into everything anyway.”

Which, fair. It had been Tony’s Plan B, after all.

According to the team, the mission had gone pretty much according to plan, other than Steve’s mutation – they hadn’t found the sceptre (unsurprisingly) but they’d found a horde of information regarding other HYDRA bases within Europe and Asia to hit next instead (this one had been surprising, actually, since HYDRA’s pretty good about keeping under the radar). They’d rolled up to the hostile that Tony’d restrained – a woman named Tilda Johnson according to SHIELD’s old databases – and put her in the quinjet once they’d salvaged everything and rounded up any of the HYDRA agents. She’d still been unconscious, but they’d found a syringe with an unknown substance inside and bagged it, quickly taking off to Landstuhl to get to Steve and Tony. They hadn’t made it but a kilometre towards the hospital when JARVIS had finally gotten their notice, directing them to Tony’s crash zone, and they’d restrained Steve – who’d gotten his teeth into Thor in the process – in one of the quinjet’s holding cells before getting Tony inside, taking off immediately and calling for Helen because of the alarming state Tony’d apparently been in.

While Tony’d been in the Cradle, Bruce and a team of biological agent specialists had gotten to work on Steve and the unknown agent in the syringe, while Clint and Natasha had worked on Johnson. The woman had been forthcoming about what had happened – apparently she was claiming that she’d ‘turned the great Captain America into a werewolf!’ in between bouts of hysterical laughter and sullen silence – but had been tight-lipped regarding the chemical composition of said substance. Bruce had tentatively come to a similar conclusion, though in more scientific terms, namely that Steve had been changed into a wolf-like creature that did admittedly run on some sort of lunar energy. According to Bruce, the substance that they’d been able to harvest heightened and waned during the moon’s cycles, and a day ago, during the new moon, Steve had mutated back into his usual self for a good fourteen hours, albeit in a great deal of pain and completely disoriented.

Not to mention a perfect recall of what had happened.

The situation with Steve was complicated, according to Bruce, and in a decidedly not-good way. Steve’s metabolism wasn’t breaking down the compound that triggered the mutation, to everyone’s collective surprise, and in the almost-five days since he’d been quarantined, he’d been violently aggressive to any and all people outside of his fourteen hours of sanity. He wouldn’t eat, wouldn’t hydrate, wouldn’t do anything but attack when anyone came into his cell for samples, and it was wreaking havoc on his body: rapid weight loss, constant aggression and stress that was unsustainable even for Steve’s impressive constitution, and hormonal imbalances that were just downright _dangerous_ if it couldn’t be regulated. The only reason Steve wasn’t already dead was because of the serum, and Bruce was pretty damn sure that it was only delaying the inevitable, because if they kept Steve in isolation without addressing the underlying issues, he probably _would_ die from the strain of it all, and likely within the week. Ultimately, unless Johnson gave up her formula or simply gave them a cure, Steve wouldn’t survive this, and she wasn’t talking.

The fourteen hours that Steve had been mutated back to his normal self gave them some insight, though, not to mention gave Steve the opportunity to rehydrate himself and gorge himself on calories for the next mutation. He’d detailed how he ran into Johnson, how it felt to mutate both into and from the wolf-like creature, and what he was feeling and experiencing while he was mutated. The others had given Steve’s inputs to Tony in flat, impersonal bullet points – making multiple, heavy-handed efforts to emphasise that Steve wasn’t a doctor and there was no scientific proof to his claims – but Tony could read between the lines: Steve had felt saner and more in control when he’d been...busy with Tony.

While he’d said that Steve had just been mutated and therefore probably hadn’t been suffering too many side-effects yet, Bruce _had_ admitted him that it made some biological sense, because the chemicals and hormones Steve either had too much or too little of in his mutated state were definitely correlating with libido as well as his aggression and anxiety. Considering what he’d instinctively and _immediately_ done to Tony once he’d mutated, they’d taken that into account within controlled environments, introducing various genders of animals and humans that were in a variety of states, including menstruation, animal heat, and chemical arousal via SHIELD-issued cocktails. None of it had worked in the slightest, Steve attacking the reinforced barrier between cells in a blind rage, and then Steve himself had echoed that it hadn’t helped once he’d regained sanity and the normal amount of legs.

All of the information had been clinical and dry, but Tony’d been able to read the undercurrent in the room, something they still weren’t telling him. For all of Tony’s faults, he’s always been good at reading people – well, except for Natasha – and he’d finally blown up, demanding the remaining piece of the puzzle being hidden from him.

And...he’s not sure what to think about what they’d eventually told him, because apparently Steve had apparently confirmed that he only wanted two things when he was mutated: to feed and fuck.

The human food, animal kibble, and dead animals hadn’t interested him at all, Bruce had said quietly, so they figured it needed to be fresh, which unmutated Steve was adamant against despite his serum-enhanced body burning through calories at a meteoric rate. Furthermore, he didn’t want to fuck just anything or anyone – according to Steve, all he wanted was _Tony_ , like some sort of impossible compulsion that had dug itself into his hindbrain like Jacob Black levels of super-creepy imprinting.

Maybe it was the fact that Tony’d been the first warm body he’d gotten his prick into, leading to some sort of pheromone link, or maybe it was something else (and Tony’s not sure how to take that, and is avoiding thinking about it), but Steve had explicitly said that nothing else was making him respond. It was also clear from bloodwork that the lack of viable food and consummated rut when he was mutated was just increasing the overload of testosterone and vasopressin while tanking his serotonin and oxytocin, amongst other hormones and chemicals that Tony hadn’t recognised, and his vitals were becoming more erratic and life-threatening in the meantime. The stretches of starvation were pretty much destroying his muscles and tissues too, Steve looking thinner and diminished every single day, and he’d been noticeably weak and less thick with muscle when he’d finally mutated back to himself.

It was killing him, the sustained starvation and lack of relief from his libido and the constant high levels of stress and anxiety, and he wasn’t going to last another week without _something_.

Tony takes a deep breath, drops his fork to his bed tray, and says to the silent room, “When—when he—well, when he _knotted_ , he was calm, y’know? Sat there and just licked his...paws, or something else on his body, or _me_. He was pretty docile when he—”

“No,” Rhodey says, and Tony swallows thickly because he wants to jump onto Rhodey’s instant demand and forget that the thought has even crossed his mind, but he can’t. He _can’t_. Steve’s going to _die_ , and Tony can’t lose one of his best friends if there’s anything in his power that he can utilise to at least help.

“James is right,” Bruce says tightly, eyes focussed on Tony’s ankle and his hands fidgeting in front of himself. “It nearly killed you, and there isn’t any evidence that it would even help Steve anyway. Even without the regulation of his hormones, it’s still unlikely that it’ll do any good with the rest of his biochemistry. Besides, do you really want to do something like that in front of SHIELD personnel—”

“I fought it the first time,” Tony interjects roughly, clears his throat, and continues in a calmer tone, “but if I don’t fight it this time—”

“ _No_ ,” Rhodey snaps.

“Steve could _die_ ,” Tony snarls.

“Steve could die _anyway_ ,” Rhodey bites back.

“You don’t _know_ that!” Tony yells. “This is all conjecture, and we need to buy him time until we figure out a cure, damn it! If being there calms him down, then maybe he’ll eat and regulate and we won’t have to _bury_ him. It’s not like I’ve done freakier shit in my life – hell, I’ve already done this exact same thing once! – and if this saves _Captain America_ , then I’m more than willing to do what I have to so he sticks around, chiding us about our nasty twenty-first century habits and laughing at cheesy sci-fi movies. What is _wrong_ with you guys? It’s a no-brainer.”

Rhodey opens his mouth to argue but he doesn’t have the chance because Bruce says quietly, “Steve’s already declined. He says that he doesn’t want you anywhere near him, even if this does kill him. He didn’t get to consent to attacking _you_ , Tony, and he was _devastated_ when he regained his normal body and remembered what happened. Besides, it’s not like you can talk it over with him now to get consent now.”

That stops Tony in his tracks.

When it comes to sexual matters, Tony’s a big advocate of consent – he’s been assaulted way too many times in his long, miserable life to think anything different ( _too many nights with alcohol and cocaine and no way to say no, too many nights being emotionally manipulated by Ty and Sunset or countless others, too many cold, dark nights in a dank cave with his hair still damp from the barrel_ ). He’s also aware that Steve’s a staunch advocate of it too – he’s done PSAs and preached on candid interviews and even once spoke in favour on a bill being passed in Congress about equal opportunity and non-discrimination no matter the time or place (Fox News had nearly shit themselves at that and still refused to even mention Captain America unless forced).

Tony hadn’t consented to what happened in Germany, but Steve hadn’t consented to the injection _or_ what happened when he’d mutated either, and he’s apparently not consenting to anything now that he’s in quarantine. That’s a big deal, for Steve _and_ for Tony, and in literally any situation Tony would take that as gospel and celebrate the boundaries being drawn.

But.

 _But_.

Tony loves Steve. He _loves_ him. He’s _in_ love with him.

He sometimes thinks he always has been.

And there isn’t anything Tony wouldn’t do for Steve Rogers, to save his life, even if it’s at the expense of his own.

They look at him with sympathetic pity, words coming out of their mouths to cut off any thoughts that Tony might have as they implore him to think of Steve’s wishes, and all Tony can do is mumble his promises ( _lies_ ) that he understands, that he won’t do anything rash, that he’s _serious_ when he says so. Except his brain is whirling with possibilities and complications, trying to figure out ways to bypass security protocol and the bodyguards and scientists that are absolutely posted at every square foot outside of Steve’s isolation pod. The security is easy, but the flesh and blood people are a different story. If SHIELD was still running, it would’ve been easy – Fury would’ve helped Tony inside in a heartbeat, because as much as they had butted heads, Fury had still been good at being pragmatic in the face of the greater good. If it could save Captain America, and if Tony gave his word that he could buy time until a cure or treatment could be developed, he’d be rational enough to deal with the immediate dangers.

It’s not just SHIELD though, instead a mixture of Tony’s staff (easily dealt with), ex-SHIELD (who could probably be brought around by Maria, who was pragmatic herself), civilian scientists (hit-or-miss, could probably be bribed or persuaded for the sake of Captain America’s life), and the rest of the Avengers. The Avengers are the problem, and Tony doesn’t know how to get around that. He’s one of the heavy hitters on the team, sure, but they’re all formidable in their own right, plus they all have the added benefit of knowing each other’s weaknesses and strong points, which would be problematic at best and downright catastrophic at worst.

He mulls and plots and tries his damndest to work out a plan as Avengers and doctors come in and out of his hospital room, coming up with ideas that he quickly throws away almost as quickly as he thinks them up, and he’s almost to the point of frustrated tears and uncontrollable screaming by the time Natasha finally makes her appearance.

“Do you love him?” he hears her husky, neutral voice ask from the shadows of his dimmed room, and he startles, blinking rapidly as his eyes snap towards the sound of her familiar voice.

He can barely see her, definitely can’t suss out her expression (not that he’d be able to read her well anyway), but doesn’t hesitate to breathe out in a weak croak, “ _Yes_.”

She studies him for a long time, her eyes only barely visible by the gleam of dimmed lights in an all-seeing gaze, and then she says, “I thought so. He loves you too, you know.”

Tony can’t hold back the snort of disbelief.

He thinks he can hear a smile in her voice when she says, “Well, you’ve always been a master at self-deprecation and denial, so I’m unsurprised by that reaction, but it’s ultimately irrelevant.” Tony opens his mouth to say something, though he’s not even sure what, but she continues quietly, “I know you have reasons to distrust me, even after all this time, but I do care about you, Tony. If I get you in there, will this kill you?”

A bright, overwhelming rush of hope flares in his chest, making him feel tight and stretched thin, and he says in a thin rush, “No, of course not, and if my vitals drop too low, you can pull me out to go through the Cradle again. There might be a bit of a fight, but Steve won’t hurt _me_ , and I think you know that. I—I don’t want to disregard what he wants, but I can’t—we can’t lose him, Nat. None of us can, the Avengers _or_ the world. We need him. _I_ need him. _Please_ , let me try, I can save him, _please_ —”

“Okay,” she says.

And suddenly the world seems just a little bit brighter.

* * *

Natasha is quite efficient, managing to clear the space for the most part.

A bare-bones staff remains, to monitor Tony’s health and bodily safety, but the rest of the crew is sent to a progress meeting and Natasha manages to be the Avenger on call, so Tony simply walks in, clad in nothing but a silk bathrobe and a shaky smile, feeling wired from adrenaline but heavy with guilt. Steve – massive and snarling and gleaming in the over-bright florescent lights illuminating his glass cell, but noticeably emaciated and obviously weak – spots him almost instantly as he walks inside, Natasha right behind him as a silent, comforting presence.

His reaction is immediate: Steve’s entire body instantly loses all of the snarling aggression in his tense, starving body, eyes focussed solely on Tony’s slow advance, and he’s whining pitifully, panting heavily. The blue of his eyes is so familiar, despite being surrounded by golden fur, and Tony wonders if he’s reading it right, if he’s really seeing _grief_ in Steve’s canine face.

Natasha brushes her hand down Tony’s arm, squeezing his hand once, before she murmurs, “You know the rules. Don’t be stupid, or we won’t let you come back in if we have to take you to the Cradle, got it?”

Tony’s not even remotely interested in _not_ being brutally honest about his physical state because Natasha’s right. If Tony hides anything, or doesn’t give the order to get out when he feels like he’s at a breaking point, they really _will_ lock Tony up in a windowless box; conversely, if he’s honest and open about _everything_ , then the others will see how _good_ this is, how Tony’s saving him and buying Steve time to survive. If it goes well – or as well as it can, at least – then there will be more Avengers on his side, like Natasha as well as Clint, Thor, and possibly even Bruce himself.

“For the first time in my life, I _promise_ I won’t fuck this up,” he says honestly. And he won’t. He loves Steve too damn much to risk his in.

“I know,” she replies quietly, squeezes his hand one last time, and then turns away with an airy _good luck_ , heading to the people in the observation booth to shadow the cell. No need for everyone to watch the show so blatantly, since they’re capable of reading their vitals without visuals, not to mention Tony’s got an implant just like Steve does that measures that sort of stuff on an internal level.

It’s...nice.

He advances to the doorway of the mantrap, which opens at his approach, but he doesn’t enter it. Instead, he looks at Steve and says through the intercom, “Steve, I know you said no and I’m sorry, you can hate me later for this, the whole _team_ can hate me for this, but I _can’t_. I’ll be okay, you hear me? We’re going to be okay.”

Steve whines, heaving himself up until his front paws are pressed against the glass, about as tall as Tony is standing up. He looks so _thin_ , and despite the desperation Tony can see in Steve’s eyes – he might be fooling himself, but he thinks he sees just as much grief and sadness as he does mindless desire – Tony’s even more resolute in his decision.

He manages to say teasingly, wiggling his eyebrows for pizzazz, “Maybe I’ll show you such a good time that you’ll thank me instead, I dunno. This is a bit out of my usual scene, obviously, but I’m still _devastatingly_ good in bed, baby. Wish I could show you that without all the...”

He trails off, listening to Steve’s whines and staring into Steve’s big, blue eyes, and then says with amusement, “Natasha says you love me, which is insane and totally irrelevant, if I’m honest – if she hadn’t helped me in here, I would’ve found another way because I’m good like that. I didn’t need her trying to sell me a pitch that’s completely impossible anyway, because I was going to do it anyway without all the manipulation, y’know? Still, I can’t blame her, I guess, moving in on my soft side. Look, what I’m trying to say is don’t be mad at her, yeah? She’s trying to help you too, and she’s making sure that I’m safe under punishment of being locked up indefinitely if I try to pull a fast one. She’s on your side, okay? Fuck, what am I even saying, you can’t even understand me right now, you’re apparently a werewolf or something and English is completely outside of your abilities right no—I’m stalling, aren’t I? Christ. It’s not because I don’t want to do this, because I actually _do_ , I’m not even nervous or anything which I think is sort of weird honestly, but I really don’t want you to...”

He trails off yet again, heart thudding madly in his chest, and then finally says heavily, “You can kick me off the team, or yell at me, or hit me, or _whatever_ when this is all over, but I can’t sit in my workshop twiddling my thumbs while you die in this cage. I _can’t_ , even if you hate me for it later, because I’d rather you hate me than die. I can’t watch you die. I can’t do it. I can’t. I _won’t_. I—I love you way too fucking much to let you die, Steve Rogers, you insufferable _ass_ , and I am going to buy you time until they find a way to reverse this and bring you back to us, to _me_. You might not be able to understand me right now but I just need you to know that.”

Tony swallows back any other words that he wants to say and then finally steps into the mantrap, pressing his palm against the glass right where Steve’s paw rests as the glass door shuts behind him silently.

The doors to Steve’s cell slide open, and Steve stalks forward.

* * *

It’s frantic at first, Tony barely managing to catch his breath in between bouts, but then it steadies.

The most remarkable thing about it all is that Steve’s calm and almost docile even when they’re physically separated, Tony going through checks by the medical staff every six knots or so, and as long as Steve can see him, he doesn’t go apeshit (that had been a trial-and-error period that they were all adamant not to repeat). Instead, he eats – which Tony can’t really bring himself to watch, even though they’d attempted the previous types of food once Steve had stabilised and found out that freshly killed meat was apparently fine – and sleeps and cleans himself (and Tony, which is abjectly horrifying considering what he’s been eating). Like any starving animal, human or otherwise, he puts on weight remarkably fast, no doubt assisted by the serum that’s still running through his blood and bones, and by the end of even the second day, he’s just as thick and heavy as he was when he first mutated. It’s both good and bad: good because Steve is still and passive when he’s sated, which means that Tony’s not _always_ on his knees and can take breaks to clean up, get an IV drip for nutrients and hydration, and occasionally even get work done on his tablet before Steve’s ready to knot again; and bad because the increased mass of him is murder on Tony’s knees and arms, Steve needing to knot at least half a dozen times before he’s sated for a short period of time.

Tony’s own body is wasted and sore, his stomach so empty now that it’s nothing but an absent ache, but between medical checks, the breaks themselves, Extremis, and once-daily visits to the Cradle (which is very quickly moved into an area directly outside Steve’s cell, so Steve can keep his eye on Tony without losing his shit), he’s in roughly good shape. The amount of come Steve’s producing is enough to mostly keep him wet, and he lubes up with a syringe when he needs to, but his body’s practically used to almost always being stuffed full at this point – it feels decidedly weird and wrong to be empty now, even though his gut still cramps from being plugged with come and his insides still feel battered.

Actually, it all feels pretty good, if Tony’s being honest. He’s dry as a bone because of all the prostate stimulation itself, and sometimes it veers into excruciating when Tony gets off despite his frantic attempts otherwise (God, but sometimes it’s fucking _impossible_ to keep his hands off his own prick, and damn anyone who’s watching), but it’s _good_. He’s pretty sure that he’s going to sleep for a goddamn week when this is all over – being constantly wrecked by prostate orgasms that occasionally explode into a full orgasm is a _hell_ of an experience, brutal and consuming and completely blinding, and between that and the bright validation that he actually _is_ helping Steve with science to back him up, it’s almost overwhelming.

There’s still a glimmer of fear though – not for the situation they’re in, not even for Steve’s condition exactly, but more like fear of Steve’s inevitable hatred and feelings of deep betrayal, courtesy of one Tony Stark. It’s going to be devastatingly painful when Steve justifiably tells him to leave, and a small, dark, hateful part of Tony wishes that he’d stay like—no. _No_. Steve getting through this, becoming _Steve_ again, is all that matters, not Tony’s desperate guilt that he’s crossed the biggest line of all.

Everything blurs together for an age, Tony forgetting how many times he’s been inside the Cradle, his body perpetually sore and raw and ravished by pleasure and guilt, until suddenly everything changes.

He’s being pummelled, Tony’s body draped over a plush and sweat-drenched stool to give his arms and chest a break, utterly surrounded by Steve’s bulk as he scrapes his teeth along the sensitive skin of Tony’s neck. His stomach is bloated from come, so much of it he can almost feel it soaking into every atom of his body, and he’s blind with pleasure, his left hand frantically jerking himself off because he can tell instinctively that Steve’s almost sated, seven loads inside him and dripping down his trembling thighs. He’s so raw that it’s physically painful to touch himself like this, but he’s incapable of stopping after hours upon hours of orgasms that tear through every nerve ending in his body, blazing and agonising and so fucking _beautiful_.

He distantly hears through the overhead comms, “ _We’ve got it! The antidote will be there in half a minute!_ ”

“Oh _fuck_ ,” Tony sobs, and the orgasm tears through him like a bomb going off, his entire body snapping up into Steve’s soft stomach and convulsing so violently around Steve’s rapidly inflating knot that he blacks out from the force of it.

He must not be out long because by the time he comes back to himself, Steve’s laid out on top of him and whining pitifully, hips carefully still despite the fact that his massive prick is throbbing inside Tony’s body, even more come mixing with the seven other loads in obvious spurts he can physically feel inside him. Tony deliriously wonders – not for the first time – if Steve’s self-aware enough to know that Tony can’t take movement against his battered, oversensitive insides when he himself has gotten off, even though it must be excruciatingly difficult for Steve to remain still while he’s coming, but the thought fades away for a long moment of blissful, post-orgasmic lassitude.

Then the door opens, and everything hits him at once.

Steve’s almost whimpering as he comes and comes and comes, massive body shaking under the strain of keeping still, but Tony can tell from the sound of it that Steve’s head is facing the door. He follows suit, blurry gaze taking in the vague shape of Bruce, Helen, and two nurses, and manages to smile even though he kind of wants to start screaming, both out of the relief and joy that Steve’s going to come _back_ and also out of fear because it’s over, and now he has to face what he’s done.

Helen and the nurses edge toward Tony but Tony croaks out around his dry tongue, “Stay there...he’s...give him a minute.”

Steve whines, shuddering all over, _still coming_ , and Tony works his hips just a little bit even though it’s oversensitive and painful. Steve whimpers, his head turning so he can nudge his nose through Tony’s damp hair, hips jerking with Tony’s movements involuntarily and riding out the last waves until he’s finally spent, both of them shuddering in the aftermath.

He can tell by the heavy, but careful heaviness of Steve’s weight that he’s done for this round, and the last knot is always the longest, a good fifteen minutes or so rather than the spare few minutes in the heat of Steve’s rut. It’s probably a good thing, because Steve’s insatiable until he’s finally spent, and he doesn’t take his prick out of Tony’s body until he’s completely done.

Tony pants and blinks rapidly past the exhaustion and mumbles nearly incoherently, “You got something?”

The nurses advance and do the usual checks – manual vitals rather than reading his internal implant’s data, manoeuvring his limbs as best they can when he’s still knotted, getting him prepped for an IV – while Bruce answers, “Natasha finally got Johnson to spill where her lab was, and the raid was earlier this morning. We found all her notes, formulas, and vials of both the compound and an antidote. I have it on me, I’m just—er—not sure exactly how to go about this?”

Tony kind of wants to laugh, because despite the fact that this certainly isn’t the first time Bruce has seen this now, it’s still distantly amusing that he’s still so weirded out by it all. It’s been days at least, probably longer, and Tony himself would’ve been inoculated by the crazy by now. Or maybe Tony’s just weirder than most, and the endorphins swirling in his blood are making him even more woozy than normal.

“If I can make a suggestion,” Tony says in a hum, eyelids fluttering as he fights the urge to sleep, “I would recommend waiting until I don’t have a knot in me, Brucie-bear. That’d be vaguely awkward, don’t you think?”

“I told you,” Helen grumbles. Then she adds in a louder voice, “We’ll wait until the penile ridge deflates and then get you out of the room—”

“I’m not leaving him right now,” Tony interjects with a bit of internal jolt, feeling nauseous at the thought.

“Naturally,” she says patiently. “We don’t want to make him panic before we can administer the injection, and you’ll need to go into the Cradle one last time in any case. We’ll do the necessary scans, see if he needs the Cradle after you, and then monitor you both for any further complications.”

“Well,” Tony says, his voice coming out strained and small, “I’d suggest two separate rooms so he doesn’t immediately come to kill me for—for taking away—for—” And to his horror, the exhaustion and bone-deep relief and endorphins and anxiety and fear and regret all release at once from the deepest pit of his heart, a hoarse sob tearing out his throat. Another one follows, then another, and suddenly he’s crying, harsh and vicious, and he can’t fucking breathe from the debilitating force of it all. He wants to curl up in a ball and sink into the floor, wants to _disappear_ , but he can’t get away from this knot or his guilt, and he just weeps, hiding his face and feeling so fucking pathetic and terrible that he’d be embarrassed at the display of weakness if he wasn’t so _tired_.

Maybe it’s a good thing that he breaks down before the knot deflates, because he’s unconscious before it goes down enough to separate them.

* * *

The first thing he sees when he opens his eyes is Natasha.

It takes him a long time to steady himself before he’s ready to address her though: he focusses on how his body’s feeling (tired and so sore he feels like he’s been thrown through a more than a few buildings, but pretty decent otherwise), how his mental capacity’s holding up (mind’s quick as usual, albeit heavy with residual sleep, and he doesn’t feel like he can’t remember anything), and if he’s on the verge of an anxiety attack or something. That last one is a bit of a doozy, but at least he can’t see Steve when he takes a look around his room, and he’s somewhat surprised to find himself in his own bedroom at the Tower rather than sequestered away on the eightieth floor, where the hospital level is. He wonders if that’s Natasha’s doing, or if the Avengers overall had decided to separate Steve and Tony by floors upon floors to stave off the inevitable carnage when Steve’s healthy enough to finally corner Tony.

 _Fuck_ , but that hurts to think about.

“How is he?” he finally asks, voice hoarse and thick with sleep, pushing himself upright as much as he can. Natasha doesn’t help and he’s thankful for it, even though it’s not exactly easy with his aching, heavy limbs.

“Back to his usual self,” she answers from his bedside, face impassive. “The serum’s helping a lot, but it’s nothing that a few night’s rest won’t fix. He’s back to normal and in relatively good shape, so he’ll be fine.”

Tony sinks back into his haphazard pile of pillows with relief, almost dizzy with it. His lifts his heavy arms and rubs his face with his hands, digging his fingers into the corners of his eyes to remove any lingering sleep, and mumbles, “Thank God, but you know that’s not what I’m asking.”

She’s quiet for a long moment, just _looking_ at him, and then she says quietly, “He’s okay, Tony. Still processing everything, I think, but that takes time. What I can say is that he’s not mad at you.” Tony snorts loudly, but Natasha continues evenly, “He’s not, actually. Confused and...I don’t think ‘disappointed’ is the right word, but he is upset that you didn’t tell him how you felt _before_ he mutated into a sex-crazed wolf.”

Tony freezes.

Natasha huffs out a sound that might be a laugh and says, “I heard what you said over the comms and while you’re not wrong in thinking that I absolutely would’ve used that tactic to give Steve a chance, you’re also not wrong that I didn’t need to. You were going to find a way regardless, so there wasn’t any tactical advantage in trying to manipulate you. I said it because you deserved to know, just in case something went wrong and we couldn’t fix him because I swear, at the rate you two were going, I’m fairly certain that both of you were going to go to the grave without saying a word. It was exhausting, not just for me but for the entire team at this point because it’s not like either one of you boys were subtle to anyone except each other.”

Tony’s torn between hysterical laughter and paralysing muteness, mouth opening and closing but throat too tight to get out a sound, and Natasha continues airily, “Though I will definitely admit that I manipulated the situation when I neglected to inform you that he was perfectly capable of understanding and remembering things people said while he was all furry, so I suppose the cat’s truly out of the bag now. Or wolf, as it were. He wants to talk to you when you’re ready, though I will also say that I will personally drag you to him if you even think about pulling a disappearing act, and I can guarantee that it will be both humiliating _and_ painful. He’ll be in Room 17 until Thursday, if everything continues on the same trajectory.”

She stands up, looking down at him for a long moment, and then presses the tips of her fingers against the top of his left wrist, a fleeting touch that disappears almost as soon as he feels it. “I am glad you’re okay Tony,” she tells him quietly, and then walks out without any fanfare, leaving him alone with his swirling, confusing, disbelieving thoughts.

* * *

It’s just as much Natasha’s threat as it is his unbearable urge to see Steve in the flesh with his own eyes.

He’s perfectly aware that Steve knows he’s here – everything in the tower is glass, including the hospital level, and while it can go opaque to block out any onlookers for privacy reasons, Steve’s eyes are so sharp that he’s always been able to somewhat see through. Furthermore, there’s also the fact that the observation room that Tony’s in has been very empty, all of Steve’s visitors simply popping in his private room to keep him company rather than sequestering themselves away. He’s not sure who else – besides perhaps Fury – would not just go inside the room to keep Steve company, since even Natasha wanders into Steve’s room.

Still, Steve doesn’t acknowledge him outside of the long, expressionless glance towards the glass that separates them. Tony’s torn between paralysing fear that Steve’s intentionally ignoring him and the desperate hope that maybe Natasha’s not completely wrong. Tony doesn’t have the best track record with reading people when it comes to any sort of positive reinforcement or emotion, and Tony’s self-aware enough to know that his own innate self-flagellation ( _thanks Dad, and Sunset, and Tiberius, and Obie, and—_ ) can get in the way of his own happiness sometimes, so it’s hard to know if Steve’s preparing to rage at him for deliberately ignoring his lack of consent.

The logical part of him can admit that Steve’s not shy when it comes to things like this, though. If Steve has a problem, he’s the type to jump into a confrontation or fight or discussion with aplomb, regardless of how uncomfortable it is. Steve’s always been good about that, letting everyone know where he’s coming from without sugar-coating anything, and Tony is tentatively comforted by that, because if Steve was truly upset or angry, Tony doesn’t think for a damned second that he _wouldn’t_ have escaped to corner Tony, and certainly wouldn’t be sitting on his bed patiently while Tony hovered just outside his room.

That being said, this is a very different situation, and Tony doesn’t know how that will translate. At the end of the day, the only people at fault are Tony himself and Tilda Johnson, with Natasha possibly added into the mix – _Steve_ hadn’t done anything wrong, as far as anyone’s concerned, and it’s certainly not Steve’s _fault_ either. Even if this looming conversation goes as badly as Tony thinks it might, Tony refuses to not communicate that to Steve directly, because he deserves that peace of mind.

Tony takes a deep breath, musters up his courage, and tries to plaster on his usual armour of easy nonchalance even as he prays to a god he doesn’t believe in that he hasn’t ruined everything, that they can be friends again, that they can continue being family, that _maybe Natasha was right_.

Tony exhales, closes his eyes briefly to brace himself, and then walks inside.

**Author's Note:**

> Left it open-ended because 1) I couldn't decide which of the three endings I envisioned would be 'The Best™'; 2) because all of you will be able to make your own judgement calls and envision what you think is right; and 3) COVID-19 sucked out every gram of my life out of my eyeballs and has left me with no time to eat or barely even shower, let alone make a final decision on an ending. I do hope it's not too disappointing, and maybe one day I'll write a companion fic with the aftermath, but as of now, this seemed like the best place to end it.
> 
> Thank you very much for reading, and take care of yourselves and loved ones. <3


End file.
